During the past five years, the HSDRC Cell Culture Core has assisted the projects of more than 100 investigators by providing services ranging from providing cryopreserved cell lines from our large culture collection, initiating keratinocyte and fibroblast cultures from biopsies of normal and hereditary skin disease tissue, generating immortal cell lines from primary cells using retroviral vectors, providing consultation and training, performing mitogen-sensitivity and specificity experiments, and serving as a center for new collaborative projects. The heavy use of Cell Culture Core resources has reinforced our belief that the research of many established and new skin disease research scientists in the Boston area, as well as all over the U.S and around the world, is aided significantly by a technical and intellectual center that can assist in the planning and execution of cell culture experiments. The considerable expense and the setup and training time necessary to generate high quality cultures of human and murine skin keratinocytes, fibroblasts, and other skin cell types for pilot experiments represents a barrier to entry for many investigators. The main objective of this Core is to overcome this barrier by providing starter samples of culture medium, cell culture methods and training, primary and immortalized Cell lines from its culture collection, and more complex services, including retroviral and adenoviral transduction of cells. Transgenic and gene knockout technology has made the living mouse a preferred model for determining the molecular basis of many skin diseases. In many cases, however, the mutant mice die in utero or soon after birth, such that cultured populations of the affected cell type must be generated to permit complete investigation. Recently published methods for serial expansion and production of spontaneously immortalized lines of mouse epidermal keratinocytes will be added to the Core's repertoire to support transgenic and knockout mouse studies. Another feature of the barrier to cell culture-based experimentation in skin biology is lack of basic microscope and digital photography equipment and skills. Training and access to conventional microscopes and digital cameras, including time-lapse photography, are new components of this core.